Incorrect scope after transform-es2015-block-scoping (T7429)

[babel-bot]

Issue originally made by Juriy Zaytsev (kangax)

Options

{ plugins: ['transform-es2015-block-scoping', {
  visitor: {
    CallExpression: function(path) {
      console.log(`
        ${path.node.callee.name} ---
        own: ${Object.keys(path.scope.bindings)}
        parent: ${Object.keys(path.scope.parent.bindings)}
      `.replace(/\s+/g, ' '));
    }
  }
}] },

Input code

function f(x) {
  let smth = x.foo;
  for (let i = 0; i; i++) {
    let n;
    if (n) return;
    g(() => n);
  }
}

Transformed with block-scoping to:

function f(x) {
  var smth = x.foo;

  var _loop = function (i) {
    var n = void 0;
    if (n) return {
        v: void 0
      };
    g(() => n);
  };

  for (var i = 0; i; i++) {
    var _ret = _loop(i);

    if (typeof _ret === "object") return _ret.v;
  }
}

Description

This outputs:

g --- own: i,n parent: x,smth,_loop,_ret
_loop --- own: parent: i

When encountering CallExpression within a loop, the scope doesn't look correct. Current scope should have _ret, i, _loop, and x bindings.